From f808c13fd3738948e10196496959871130612b61 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Fri, 8 Sep 2017 16:15:08 -0700 Subject: lib/interval_tree: fast overlap detection MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Allow interval trees to quickly check for overlaps to avoid unnecesary tree lookups in interval_tree_iter_first(). As of this patch, all interval tree flavors will require using a 'rb_root_cached' such that we can have the leftmost node easily available. While most users will make use of this feature, those with special functions (in addition to the generic insert, delete, search calls) will avoid using the cached option as they can do funky things with insertions -- for example, vma_interval_tree_insert_after(). [jglisse@redhat.com: fix deadlock from typo vm_lock_anon_vma()] Link: http://lkml.kernel.org/r/20170808225719.20723-1-jglisse@redhat.com Link: http://lkml.kernel.org/r/20170719014603.19029-12-dave@stgolabs.net Signed-off-by: Davidlohr Bueso Signed-off-by: Jérôme Glisse Acked-by: Christian König Acked-by: Peter Zijlstra (Intel) Acked-by: Doug Ledford Acked-by: Michael S. Tsirkin Cc: David Airlie Cc: Jason Wang Cc: Christian Benvenuti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/interval_tree_test.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'lib/interval_tree_test.c') diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c index df495fe81421..0e343fd29570 100644 --- a/lib/interval_tree_test.c +++ b/lib/interval_tree_test.c @@ -19,14 +19,14 @@ __param(bool, search_all, false, "Searches will iterate all nodes in the tree"); __param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint"); -static struct rb_root root = RB_ROOT; +static struct rb_root_cached root = RB_ROOT_CACHED; static struct interval_tree_node *nodes = NULL; static u32 *queries = NULL; static struct rnd_state rnd; static inline unsigned long -search(struct rb_root *root, unsigned long start, unsigned long last) +search(struct rb_root_cached *root, unsigned long start, unsigned long last) { struct interval_tree_node *node; unsigned long results = 0; -- cgit v1.2.3